JP6482313B2 - RESISTANT PASTE AND ITS MANUFACTURING METHOD, RESISTANT AND USE THEREOF - Google Patents

Description

  The present invention has a volume resistivity in the range of low / medium resistance of 200 μΩ · cm (surface resistance of 10 μm thickness 200 mΩ / □) or more, and a resistance having copper (Cu) / nickel (Ni) based metal as a conductive component. The present invention relates to a body paste, a resistor paste, a manufacturing method thereof, a resistor obtained using the paste, and a use thereof.

Conventionally, as a thick film resistor having a low / medium resistance of about 200 mΩ / □ to 100Ω / □, a terminal electrode portion made of a noble metal paste mainly composed of silver (Ag) and palladium (Pd), and ruthenium oxide (RuO). A thick film resistor formed by a resistor made of a resistor paste containing ₂ ) as a main component is known. However, the noble metal paste is expensive, and there are concerns about problems such as a decrease in reliability of the terminal electrode connection portion due to solder erosion and electromigration of Ag.

  To solve this problem, it is conceivable to use a Cu electrode formed of a conductive paste containing Cu as a main component (conductive component) as the terminal electrode part. However, ruthenium oxide must be fired in the air. Cannot be combined with Cu electrodes. That is, if the ruthenium oxide paste is fired in the air, the Cu electrode is oxidized, and if fired in nitrogen, the ruthenium oxide is reduced and the resistance becomes unstable. In order to avoid such a problem, a base metal resistor paste mainly composed of copper and nickel has been proposed as a resistor paste.

  Japanese Patent No. 3642100 (Patent Document 1) discloses an insulating substrate, a resistance layer made of a copper / nickel alloy formed on at least one surface of the insulating substrate, and the resistance layer on a pair of opposite ends of the insulating substrate. In a chip resistor having an end face electrode provided so as to connect, a thick layer resistor paste made of copper powder, glass frit and organic vehicle components is printed on a copper / nickel alloy powder and fired to form A chip resistor comprising an alloy layer is disclosed. This document describes that the glass frit component is 0.5 to 10% by weight with respect to the metal component. Further, it is described that the object is to provide a low-resistance thick film resistor having a resistance of 1Ω or less, particularly 100 mΩ or less, and in the examples, a resistor having a resistance value of 10 to 100 mΩ is manufactured.

  JP 2010-129896 A (Patent Document 2) discloses a paste containing at least a conductive metal powder composed of copper powder and nickel powder, glass powder, and a vehicle containing a resin and a solvent. The glass powder comprises a first glass powder containing 70% by mass or more of bismuth in terms of oxide, and a second glass powder substantially free of lead and cadmium. A paste is disclosed. In this document, it is described that the blending amount of the first glass powder is preferably in the range of 0.5 to 10 parts by mass with respect to 100 parts by mass of the conductive metal powder. Has been. Moreover, the compounding quantity of 2nd glass powder describes that the range of 2-10 mass parts is preferable with respect to 100 mass parts of electroconductive metal powder, and 1-10 mass parts is mix | blended in the Example. Moreover, it is described that the volume resistivity of the resistor film obtained by firing the resistor paste is 20 to 200 μΩ · cm, and in the examples, a resistor film of 37 to 126 μΩ · cm is manufactured.

  These resistor pastes have a small temperature coefficient and are useful as resistor pastes. However, since the resistance of the resistor film formed from these resistor pastes is relatively low, it cannot be used for low / medium resistance applications of 200 mΩ / □ or more. The present inventors examined increasing the ratio of the glass particles. However, since glass melts and flows during firing, the shape of the resistive film after firing collapses, or the glass melts and flows during firing. By concentrating on the surface, the conduction path is blocked or blocked, and a stable resistance value cannot be obtained.

  In Japanese Patent No. 3559160 (Patent Document 3), a conductive powder made of a mixed powder of copper powder and nickel powder or a conductive powder made of Cu-Ni alloy powder and 3 parts by weight with respect to 100 parts by weight of the conductive powder. 20 parts by weight of a glass powder containing no Pb and Cd as components and ZnO and / or BaO as a main component, and 1 to 10 parts by weight of copper oxide powder with respect to 100 parts by weight of the conductive powder Is disclosed in which a conductive paste is dispersed in an organic resin as a vehicle and a solvent such that the ratio of the conductive component is 75 to 90% by weight. This document describes that the glass powder is necessary for adhering the thick film resistor to the ceramic substrate and adjusting the resistance value. In the embodiment, a thick film resistor having a sheet resistance of 25 to 40 mΩ / □ is manufactured.

  However, the resistance film formed by this resistor paste has a low resistance and cannot be used for low / medium resistance applications of 200 mΩ / □ or more. Further, since the copper oxide powder that is non-conductive particles is included, it is difficult to develop a uniform resistance value, and even if the resistance value is increased, the resistance value is likely to vary.

Japanese Patent No. 3642100 (Claims, paragraph [0008], Examples) JP 2010-129896 A (claims, paragraphs [0025] and [0027], examples) Japanese Patent No. 3559160 (Claim 1, Paragraph [0019], Example)

  Accordingly, an object of the present invention is to provide a resistor paste capable of suppressing variations in resistance value even when the resistivity is low or medium resistance of a volume resistivity of 200 μΩ · cm (surface resistance of 200 μm thickness: 200 mΩ / □) or more, and a method for manufacturing the same. And providing a resistor and its use.

  Another object of the present invention is to provide a resistor paste having a small resistance value temperature dependency or resistance value temperature coefficient (TCR) and having a stable resistance value, a method for manufacturing the resistor paste, a resistor, and a use thereof.

  Still another object of the present invention is to provide a resistor paste that can be fired in an inert gas atmosphere such as a nitrogen atmosphere, has high strength even when fired at a high temperature, and can form a thick film while suppressing pattern collapse and swelling. It is in providing the manufacturing method, a resistor, and its use.

  Another object of the present invention is to provide a resistor paste capable of forming a thick film firmly adhered to a substrate, a method for manufacturing the resistor paste, a resistor, and a use thereof.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that a conductive component formed of a metal containing copper and nickel, a resistance adjusting component formed of non-conductive inorganic particles, an inorganic binder, and an organic vehicle. In the resistor paste including the above, by forming the composite particles by coating the non-conductive inorganic particles with a metal, the volume resistivity is 200 μΩ · cm (surface resistance of 10 μm film thickness 200 mΩ / □) or more. However, the present inventors have found that the variation in resistance value can be suppressed and completed the present invention.

  That is, the resistor paste of the present invention includes a conductive component formed of a metal including copper and nickel, a resistance adjusting component formed of non-conductive inorganic particles that are not melted or thermally decomposed at the firing temperature, and a firing temperature. A resistor paste comprising an inorganic binder formed of low melting point glass particles having a low softening point and an organic vehicle for dispersing these components, wherein at least a part of the conductive component is the resistance adjusting component. By covering at least a part, composite particles in which at least a part of the surface of the non-conductive inorganic particles is coated with the conductive layer are formed. The conductive layer may contain copper and / or nickel. The conductive layer may cover 50% or more of the entire surface of the nonconductive inorganic particles. The conductive layer may have a thickness of about 0.05 to 5 μm. The conductive layer may be formed by electroless plating. The conductive component may further contain metal particles. Moreover, the resistor paste of the present invention may further contain non-conductive inorganic particles that are not covered with the conductive layer. The volume ratio of the conductive component may be about 10 to 80% by volume with respect to the total volume of the conductive component, the inorganic binder component, and the resistance adjusting component. The volume ratio of the resistance adjusting component may be about 1 to 75% by volume with respect to the total volume of the conductive component, the inorganic binder component, and the resistance adjusting component. The volume ratio of the inorganic binder component may be about 5 to 50% by volume with respect to the total volume of the conductive component, the inorganic binder component, and the resistance adjusting component. The center particle diameter (D50) of the non-conductive inorganic particles (the non-conductive inorganic particles coated with the conductive layer and the non-conductive non-conductive inorganic particles) may be about 0.05 to 20 μm. The non-conductive inorganic particles may be spherical. Further, the non-conductive inorganic particles may be metal oxide particles. The conductive component may be an alloy of copper and nickel, or may be at least two selected from the group consisting of copper, nickel, and an alloy of copper and nickel. In the conductive component, the mass ratio of copper and nickel may be about copper / nickel = 90/10 to 30/70. The resistor paste of the present invention may have an absolute value of resistance value temperature dependency (TCR) of the fired resistor of 300 ppm / ° C. or less.

  The present invention also includes a method for manufacturing a resistor including a firing step in which the resistor paste is fired at a temperature equal to or higher than the softening point of the low-melting glass particles in an inert gas atmosphere such as nitrogen gas.

  The present invention also includes a resistor obtained by the manufacturing method. The present invention also includes a thick film resistor and an electronic component provided with the resistor.

  In the present invention, in a resistor paste including a conductive component formed of a metal containing copper and nickel, a resistance adjusting component formed of nonconductive inorganic particles, an inorganic binder, and an organic vehicle, the nonconductive inorganic particles are metal. Since the composite particles are formed by being coated with, a variation in resistance value can be suppressed even with a low / medium resistance having a volume resistivity of 200 μΩ · cm or more. In addition, a resistance film (particularly a thick film) having a small TCR and a stable resistance value can be formed. In addition, when the conductive component contains copper particles and nickel particles, a thick film that can be fired in an inert gas atmosphere such as a nitrogen atmosphere, has high strength even when fired at a high temperature, and suppresses pattern collapse and swelling is formed. it can. Furthermore, by including a specific proportion of the inorganic binder, a thick film that is firmly adhered to the substrate can be formed.

[Resistor paste]
The resistor paste of the present invention includes a conductive component formed of a metal including copper and nickel, a resistance adjusting component formed of non-conductive inorganic particles that do not melt or pyrolyze at the firing temperature, and a softening lower than the firing temperature. An inorganic binder formed of low-melting glass particles having dots and an organic vehicle for dispersing these components are included.

(Conductive component)
The conductive component is formed of a metal containing copper and nickel, and forms an electrical conduction path in the fired resistor. In the present invention, at least a part of the conductive component forms composite particles by coating the surface of non-conductive inorganic particles that are resistance adjusting components, as will be described later. In the paste film, the conductive component, the resistance adjusting component and the inorganic binder component exist in a mixed state, but at least a part of the conductive component is included as a conductive layer (metal layer) covering the non-conductive inorganic particles. As a result, even when the volume ratio of the same conductive component is used, the conductive components are more likely to be adjacent to each other as compared with the case of only metal particles, and therefore, the conductive components are easily sintered and a resistor having a small variation in resistance value is obtained. It is done.

  The metal constituting the conductive component only needs to contain copper and nickel in order to form a copper-nickel alloy resistor, and may further contain other metals. Examples of other metals include transition metals (for example, periodic table Group 4A metals such as titanium and zirconium; periodic table Group 5A metals such as vanadium and niobium; periodic table Group 6A metals such as molybdenum and tungsten; manganese; Periodic table Group 7A metals such as iron, cobalt, ruthenium, rhodium, palladium, rhenium, iridium, platinum, etc .; Periodic table Group 1B metals such as silver, gold, etc.), periodic table Group 2B metal (for example, zinc, cadmium, etc.), periodic table group 3B metal (for example, aluminum, gallium, indium, etc.), periodic table group 4B metal (for example, germanium, tin, lead, etc.), periodic table 5B Group metals (for example, antimony, bismuth, etc.). These metals can be used alone or in combination of two or more, and may be an alloy. The proportion of the other metal may be 50% by mass or less (for example, 0 to 50% by mass) in the metal particles, for example, 30% by mass or less, preferably 10% by mass or less, more preferably 5% by mass or less. (For example, 0.1-5 mass%) may be sufficient. The metal particles are usually made of only copper and nickel because they are inexpensive and excellent in conductivity.

  The conductive component formed only of copper and nickel is an alloy of copper and nickel, or at least two selected from the group consisting of copper, nickel and an alloy of copper and nickel (for example, copper and nickel) A combination of copper and / or nickel and the above alloy), and is usually a combination of copper and nickel from the viewpoint of simplicity.

  In the conductive component, the mass ratio of copper and nickel is, for example, copper / nickel = 90 / 10-30 / 70, preferably 80 / 20-40 / 60, more preferably 70 / 30-50 / 50 (particularly 65 / 35 to 55/45). If the mass ratio of copper and nickel is too large or too small, the resistance temperature dependency (TCR) increases. On the other hand, within the above range, the resistance temperature dependency (TCR) of the copper-nickel alloy resistor can be controlled to a sufficiently low range. However, in the present invention, a large amount of resistance adjusting component is added in addition to the inorganic binder component. May be added. Therefore, although it is assumed that the TCR changes from the TCR of the original copper nickel alloy resistor due to these components, in the present invention, the TCR of the original copper nickel alloy resistor is maintained. The reason is that the inorganic binder component and the resistance adjusting component are electrically insulative, so that they do not have an electrical effect on the conduction path formed by the sintered metal network, and the thermochemically high temperature. Because it is stable to the extent that it does not affect the composition, in fact, the TCR of the copper-nickel alloy resistor is almost unaffected and expresses the original low TCR. It can be estimated that there is. In the present specification, the low TCR means a TCR that has an absolute value of approximately 500 ppm / ° C. or less and can be actually used as a resistor.

  At least a part of the conductive component forms a conductive layer of the composite particle as described above. Although all of the conductive components may be formed of the conductive layer (metal layer), metal particles (conductive particles) can be formed from the point of being able to form a thick film with high strength and suppressed pattern collapse and swelling even when fired. ) May be included. When the conductive component forms both the metal layer and the metal particles, copper and nickel may be included in either or both.

  The shape of the metal particles is not particularly limited, and is spherical (true or nearly spherical), ellipsoidal (elliptical sphere), polygonal (polygonal, such as polygonal pyramid, tetragonal, rectangular parallelepiped, etc.), plate It may be in the form of a flat shape (such as a flat shape, a scale piece or a thin piece), a rod shape or a rod shape, a fiber shape or an indefinite shape. The shape of the metal particles is usually spherical, ellipsoidal, polygonal, indeterminate.

  The particle size of the metal particles is not particularly limited, but a large amount of non-conductive components (inorganic binder component and resistance adjusting component) are blended. For example, copper particles and nickel particles are used as separate metal particles. In this case, it is advantageous to use metal particles having a small particle size from the viewpoint of uniform dispersibility and alloying during firing. On the other hand, when using alloy particles of copper and nickel, although there is no problem in the uniformity of alloying, it is advantageous to use alloy particles having a small particle size in the same manner from the viewpoint of dispersibility.

  The central particle diameter (D50) of the metal particles is, for example, about 0.05 to 10 μm, preferably 0.08 to 8 μm, and more preferably about 0.1 to 5 μm (particularly 0.2 to 3 μm). If the particle size of the metal particles is too small, the economic efficiency is lowered and the dispersibility in the paste is also lowered, and if too large, the printability and dispersibility of the paste and the uniformity of alloying are lowered.

  The proportion of the metal particles (conductive particles) in the conductive component may be, for example, 95% by mass or less, for example, about 10 to 95% by mass, preferably about 10 to 90% by mass with respect to the entire conductive component. . When the ratio of the metal particles is too large, the ratio of the metal layer covering the non-conductive inorganic particles decreases, and the resistance value tends to vary greatly. On the other hand, if the amount is too small, the sinterability between the metal layers is slightly lower than that of the metal particles, so that the sintering is difficult to proceed, and the film is somewhat brittle and easily cut.

  The volume ratio of the conductive component can be selected from a range of about 5 to 85% by volume, for example, 10 to 85% by volume, preferably 15 to 83% with respect to the total volume of the conductive component, resistance adjusting component and inorganic binder component. It is about volume% (for example, 20-80 volume%), More preferably, it is about 25-75 volume% (especially 50-75 volume%). When the volume occupied by the conductive component is too large, the resistance value of the resistor is too low, and when it is too small, it is difficult to obtain stable conductivity.

(Resistance adjustment component)
The resistance adjusting component is formed of non-conductive inorganic particles. The resistance adjusting component is blended in order to reduce the content of the conductive component in the fired resistor to increase the resistance value, and to suppress the melt flow of the low melting point glass and prevent disconnection of the conductive path. That is, the resistance adjusting component has a function of suppressing excessive flow and segregation of the inorganic binder component and stably improving the resistance value while maintaining the shape of the fired resistive film. In addition, the resistance adjusting component also has a role of suppressing decomposition gas and the like from being confined by the molten glass and swelling of the fired film.

  Furthermore, pattern collapse occurs when a large amount of low-melting glass particles are softened and melted during firing, and cannot be retained only on the surface of the metal particles, but spread more greatly than the predetermined pattern printed on the substrate. In the present invention, by adding a certain amount or more of the resistance adjusting component (non-conductive inorganic particles), the blending amount of the low-melting glass particles can be reduced, so that a fired resistor film having no pattern spread can be obtained.

  Moreover, the swell of the fired film is caused by confining the decomposition gas of the binder resin added as an organic vehicle by the glass melted during firing. Although the binder resin is selected and blended with a resin that is easily decomposed, decomposition is likely to be delayed by firing in a nitrogen atmosphere, and the temperature at which the resin completely decomposes rises to near or above the softening temperature of the glass. Such blistering is likely to occur when the molten glass is continuously connected and there is no place where gas can escape. In the present invention, by adding non-conductive inorganic particles, it is necessary for the glass to wet and spread on the surface of the non-conductive inorganic particles, so that the action delays the formation of the continuous film or the continuous film itself. Since it becomes difficult, it can be estimated that the gas is easily released. When non-conductive inorganic particles are not included, pattern collapse tends to occur when the proportion of the glass component exceeds 40% by volume, and swelling tends to occur when the ratio exceeds 20% by volume.

  The non-conductive inorganic particles may be non-conductive and do not melt or pyrolyze (or collapse) at the firing temperature. That is, the non-conductive inorganic particles may have a softening point lower than the firing temperature, as long as the non-conductive inorganic particles can maintain the particle shape without melting or collapsing at the firing temperature. It has a melting point or thermal decomposition temperature higher than the firing temperature, for example, a melting point or thermal decomposition temperature higher than the firing temperature by 100 ° C. or higher (for example, 100 to 2000 ° C.), preferably 200 ° C. or higher (preferably higher than the firing temperature ( For example, it may be a melting point or thermal decomposition temperature higher by 200 to 1500 ° C., more preferably 300 ° C. or higher (for example, 300 to 1200 ° C.) higher than the firing temperature. Specifically, the melting point or thermal decomposition temperature of the non-conductive inorganic particles is 1000 to 3000 ° C., preferably 1200 to 2500 ° C., more preferably about 1500 to 2200 ° C. When the melting point or the thermal decomposition temperature is too low, excessive flow (movement) occurs, and the uniformity of the shape and resistance value of the resistor decreases.

Non-conductive inorganic particles include materials having a high melting point and are not easily reduced, such as carbides (silicon carbide SiC, boron carbide B ₄ C, titanium carbide TiC, tungsten carbide WC, diamond, etc.), nitrides (silicon nitride). Si ₃ N ₄ , aluminum nitride AlN, titanium nitride TiN, boron nitride BN, carbon nitride C ₃ N _4, etc., oxide (silica SiO ₂ , alumina Al ₂ O ₃ , zinc oxide ZnO, copper oxide Cu ₂ O or CuO , titanium oxide TiO _2, zirconium oxide ZrO, calcium oxide CaO, magnesium oxide MgO, metal oxides such as beryllium oxide _{BeO, CaAl 2 O 4, CaTiO} 3, CaZrO 3, MgAl 2 O 4, MgTiO 3, MgZrO 3, ZnAl ₂ O ₄ , ZnSiO ₄ and other metal composite oxides Etc.) and the like. These non-conductive inorganic particles can be used alone or in combination of two or more. When non-conductive inorganic particles are formed of these materials, they are stable even when fired in a high-temperature inert atmosphere, do not lose shape due to melting, and are metallized by reduction and sintered with copper nickel or alloys There is also no risk of affecting the electrical characteristics due to the process. Of these, alumina, silica, titanium oxide, and silicon carbide are particularly preferable because they are readily available at low cost, are chemically stable, and the plating process can be selected flexibly.

  The shape of the non-conductive inorganic particles is not particularly limited, and may be spherical (true or nearly spherical), ellipsoidal (elliptical sphere), polygonal (polygonal, tetragonal, rectangular parallelepiped, etc.) ), Plate-like or flake-like (flat, scale-like or flake-like), rod-like or rod-like, fiber-like or needle-like, or indefinite shape. Of these shapes, a spherical shape (true spherical shape or substantially spherical shape) is preferable from the viewpoint of dispersibility in the paste and reproducibility of the resistance value adjusting effect. Spherical particles are easier to disperse than other shaped particles and have no anisotropy, so that a stable resistance adjustment effect can be obtained.

  The particle size of the nonconductive inorganic particles is not particularly limited, but the central particle size (D50) of the nonconductive inorganic particles is, for example, 0.05 to 20 μm, preferably 0.1 to 15 μm (for example, 0.2 ˜12 μm), more preferably about 0.5 to 10 μm (especially 1 to 7 μm). If the particle size of the non-conductive inorganic particles is too small, there is an effect of improving the resistance value, but if high resistance is required, it is necessary to add a large amount of non-conductive inorganic particles, and the printability of the paste is reduced. It tends to decrease or the variation in resistance value increases. In addition, since small particles tend to aggregate, it is likely that only a part of the conductive component film can be formed. On the other hand, if it is too large, the printability of the paste is lowered, the smoothness of the resulting resistive film is likely to be lowered, and pattern collapse and swelling are likely to occur.

  As will be described later, at least a part of the resistance adjusting component is coated with a conductive layer to form composite particles, but the entire resistance adjusting component may be covered with a conductive layer (metal layer). Any of them may include an uncoated resistance adjusting component (non-covering resistance adjusting component). The proportion of the non-covering resistance adjusting component may be, for example, 90% by mass or less (for example, 0 to 90% by mass) with respect to the entire resistance adjusting component, for example, 0 to 80% by mass, preferably 0 to 70%. It is about mass% (for example, 5-60 mass%), More preferably, it is about 0-50 mass% (for example, 10-30 mass%). If the proportion of the non-covering resistance adjusting component is too large, the variation in resistance value tends to increase.

  The volume ratio of the resistance adjusting component can be selected from a range of about 1 to 75% by volume with respect to the total volume of the conductive component, the resistance adjusting component and the inorganic binder component, for example, 5 to 70% by volume, preferably 10 to 10% by volume. It is about 60% by volume, more preferably about 15 to 55% by volume (particularly 20 to 50% by volume). If the volume occupied by the resistance adjusting component is too large, the resistance value is too high and the stability is lowered. On the other hand, if the volume occupied by the resistance adjusting component is too small, the conductivity increases, and it becomes difficult to stably obtain a resistance value of 200 μΩ · cm or more, and pattern collapse and swelling are likely to occur.

  The mass ratio of the resistance adjusting component is, for example, about 1 to 200 parts by mass, preferably 2 to 150 parts by mass, more preferably about 5 to 120 parts by mass (particularly 10 to 100 parts by mass) with respect to 100 parts by mass of the conductive component. It is.

  The volume ratio between the resistance adjusting component and the inorganic binder component can be selected from the range of resistance adjusting component / inorganic binder component = 20/1 to 1/20, for example, 15/1 to 1/10, preferably 10/1. ˜1 / 5, more preferably about 8/1 to 1/3 (particularly 7/1 to 1/1). When the ratio of the resistance adjusting component is too large, the inorganic binder component is relatively reduced, so that the solidification becomes insufficient and the brittleness tends to be brittle. On the other hand, if the amount is too small, pattern collapse and swelling are likely to occur.

(Composite particles)
At least a part of the resistance adjusting component forms composite particles having a conductive layer (metal layer) in which at least a part of the surface is coated with a metal.

  The composite particles only have to cover the surface of the non-conductive inorganic particles with a conductive layer in general, and may not be completely covered with the conductive layer. The coverage (area ratio) by the conductive layer is, for example, 50% or more, preferably 70% or more, more preferably 90% or more, and substantially 100% of the entire surface of the non-conductive inorganic particles. It is particularly preferable. If the area covered by the conductive layer is too small or discontinuous, the effect of stabilizing the resistance value tends to be low.

  Although the thickness of a conductive layer is not specifically limited, For example, 0.05-5 micrometers, Preferably it is 0.075-4 micrometers, More preferably, it is about 0.1-3 micrometers. When the thickness of the conductive layer is extremely thin, the sinterability between the conductive components decreases. When it is extremely thick, the volume ratio of the conductive component in the paste becomes too large, and only a low resistance can be obtained.

  As a method of directly measuring the thickness of the conductive layer, there is a method of measuring a cross section of the composite particle from an image (SEM image) taken with a scanning electron microscope. In this method, first, the composite particles are embedded in an epoxy resin and cured, and after cutting with a diamond blade, the sample is adjusted so that the cross section of the particles is exposed. Next, the exposed cross section of the composite particle is photographed with the length scale displayed, and finally the thickness of the conductive layer can be read from the SEM image. However, this method is very local and generally evaluates only one particle, and is not suitable for representing the entire composite particle powder in which many particles are collected. Although it is possible to represent the whole by performing many measurements and averaging them, it is not reasonable because it requires a lot of labor for sample preparation and the like. Therefore, this method is performed only for confirming the existence of the conductive layer and grasping the rough thickness, and for evaluating the average film thickness, a method is used in which calculation is performed using the weight difference before and after the formation of the conductive layer. For that reason, the thickness of the conductive layer of the present invention is measured based on the mass ratio of the conductive layer and the nonconductive inorganic particles, and the conductive layer uniformly covers the entire surface of the nonconductive inorganic particles. Is the average thickness.

  The method of forming the conductive layer is not particularly limited. For example, an electroless plating method in which a metal is deposited from a solution of metal ions by applying a catalyst to the surface of non-conductive inorganic particles, or a metal fine particle dispersion is non-conductive. A method of forming a film by heat treatment after coating on the surface of the conductive inorganic particles, a method of coating the non-conductive inorganic particles spread thinly on the surface of the support with metal atoms jumping out of the sputtering target, and the like can be selected. Among these methods, the electroless plating method is preferable because an inexpensive process and a large amount of treatment are possible. The electroless plating method is not particularly limited, and may be performed under conventional conditions depending on the plating type.

(Inorganic binder component)
The inorganic binder component is formed of low melting point glass particles. The inorganic binder component improves the wettability with respect to the substrate and the like, improves adhesion, and is blended to form a tough resistor by melting and solidifying the entire resistance film. It also has a role.

  The low-melting glass particles only have to have a softening point lower than the firing temperature, but the softening point of the low-melting glass particles is, for example, 100 ° C. or higher than the firing temperature from the point that a tough resistor can be formed. (For example, 100-600 ° C) low softening point, preferably 200 ° C or higher (eg, 200-500 ° C) lower than the firing temperature, more preferably 300 ° C or higher (eg, 300-400 ° C) than the firing temperature ) It may be a low softening point. Specifically, the softening point of the low-melting glass particles is 400 to 800 ° C, preferably 420 to 700 ° C, more preferably about 450 to 600 ° C. When the softening point is too high, the melt fluidity is lowered, so that the adhesion and the uniformity of the resistance film are lowered. In particular, when the softening point is close to the firing temperature, the glass does not flow sufficiently, and the conductive component and resistance adjusting component cannot be connected and hardened together, so that the formed film becomes brittle, handling properties and practicality in post-processing Tends to decrease.

  The low-melting glass particles only need to have the softening point, but usually contain other oxides in addition to silicon oxide. Examples of other oxides include other metal oxides (for example, alkali metal oxides such as lithium oxide, sodium oxide, and potassium oxide; alkaline earth metal oxides such as magnesium oxide, calcium oxide, strontium oxide, and barium oxide). Periodic table group 4A metal oxides such as titanium oxide and zirconium oxide; periodic table group 6A metal oxides such as chromium oxide; periodic table group 8 metal oxides such as iron oxide; periodic table group 2B metals such as zinc oxide Oxides; periodic table group 3B metal oxides such as aluminum oxide; periodic table group 4B metal oxides such as tin oxide and lead oxide; periodic table group 5B metal oxides such as bismuth oxide), boron oxide and the like. . These other oxides can be used alone or in combination of two or more. Of these oxides, they often contain barium oxide, zinc oxide, lead oxide, bismuth oxide, boron oxide, and the like.

  Examples of the low melting point glass particles formed of the oxide include conventional low melting point glass particles such as borosilicate glass particles, zinc borosilicate glass particles, zinc glass particles, bismuth glass particles, and lead glass particles. Etc. These low melting point glass particles can be used alone or in combination of two or more. Of these low-melting glass particles, zinc-based glass particles, bismuth-based glass particles, and the like are widely used.

  The shape of the low-melting-point glass particles is not particularly limited, and is spherical (true or nearly spherical), ellipsoidal (elliptical sphere), polygonal (polygonal, such as polygonal pyramid, tetragonal, rectangular parallelepiped, etc.) , Plate shape (flat, scale or flake shape), rod shape or rod shape, fiber shape, indeterminate shape, etc. The shape of the low-melting glass particles is usually spherical, ellipsoidal, polygonal, indeterminate.

  The center particle diameter (D50) of the low-melting glass particles is not particularly limited, and is, for example, about 0.1 to 20 μm, preferably about 0.5 to 10 μm, more preferably about 1 to 5 μm (particularly 2 to 4 μm). If the particle size of the low melting point glass particles is too small, the dispersibility in the paste is lowered, and if it is too large, uniform mixing with the conductive component and the resistance adjusting component becomes difficult.

  The volume ratio of the inorganic binder component can be selected from the range of about 4 to 53% by volume with respect to the total volume of the conductive component, resistance adjusting component and inorganic binder component, for example, 5 to 50% by volume, preferably 6 to 5%. It is 40 volume%, More preferably, it is about 8-30 volume% (especially 10-25 volume%). In the present invention, even if the ratio of the inorganic binder component is large, the resistance value of the fired body can be made uniform, and the volume ratio of the inorganic binder component is the sum of the volume of the conductive component, resistance adjusting component and inorganic binder component, For example, 15-50 volume%, 20-45 volume%, More preferably, 25-43 volume% (especially 30-40 volume%) may be sufficient. If the volume occupied by the inorganic binder component is too large, the amount of glass is too large and it becomes difficult to maintain the shape of the fired resistor, and it is difficult to degas at the time of firing. Values vary greatly and breaks easily. On the other hand, if the volume occupied by the inorganic binder component is too small, it becomes difficult to ensure the strength of the fired film and the adhesion between the fired film and the substrate.

  The mass ratio of the inorganic binder component is, for example, 1 to 50 parts by mass, preferably 2 to 45 parts by mass, and more preferably 3 to 40 parts by mass (particularly 5 to 30 parts by mass) with respect to 100 parts by mass of the conductive component. It is.

(Organic vehicle)
The organic vehicle may be a conventional organic vehicle used as an organic vehicle of a resistor paste containing metal particles, for example, an organic binder and / or an organic solvent. The organic vehicle may be either an organic binder or an organic solvent, but is usually a combination of an organic binder and an organic solvent (dissolved material of an organic binder with an organic solvent).

The organic binder is not particularly limited. For example, thermoplastic resins (olefin resins, vinyl resins, acrylic resins, styrene resins, polyether resins, polyester resins, polyamide resins, cellulose derivatives, etc.), And thermosetting resins (thermosetting acrylic resins, epoxy resins, phenol resins, unsaturated polyester resins, polyurethane resins, etc.). These organic binders can be used alone or in combination of two or more. Of these organic binders, resins that burn out easily during the baking process and have a low ash content, such as acrylic resins (polymethyl methacrylate, polybutyl methacrylate, etc.), cellulose derivatives (nitrocellulose, ethyl cellulose, butyl cellulose, cellulose acetate) Etc.), polyethers (polyoxymethylene, etc.), rubbers (polybutadiene, polyisoprene, etc.), etc. are widely used. From the viewpoint of thermal decomposability, poly (meth) acrylate and poly (meth) acrylate butyl Poly (meth) acrylic acid C _1-10 alkyl esters such as

The organic solvent is not particularly limited as long as it is an organic compound that imparts an appropriate viscosity to the resistor paste and can be easily volatilized by drying after the resistor paste is applied to the substrate. It may be. Examples of such organic solvents include aromatic hydrocarbons (such as paraxylene), esters (such as ethyl lactate), ketones (such as isophorone), amides (such as dimethylformamide), and aliphatic alcohols (such as octanol and decanol). , Diacetone alcohol, etc.), cellosolves (such as methyl cellosolve, ethyl cellosolve), cellosolve acetates (such as ethyl cellosolve acetate, butyl cellosolve acetate), carbitols (such as carbitol, methyl carbitol, ethyl carbitol), carbitol Acetates (ethyl carbitol acetate, butyl carbitol acetate), aliphatic polyhydric alcohols (ethylene glycol, diethylene glycol, dipropylene glycol, butanediol, triethylene glycol) Coal, glycerin, etc.), alicyclic alcohols [eg, cycloalkanols such as cyclohexanol; terpene alcohols such as terpineol and dihydroterpineol (monoterpene alcohols, etc.)], aromatic alcohols (eg, metacresol), Aromatic carboxylic acid esters (dibutyl phthalate, dioctyl phthalate, etc.), nitrogen-containing heterocyclic compounds (dimethyl imidazole, dimethyl imidazolidinone, etc.) and the like can be mentioned. These organic solvents can be used alone or in combination of two or more. Among these organic solvents, alicyclic alcohols such as terpineol and C _1-4 alkyl cellosolve acetates such as butyl carbitol acetate are preferable from the viewpoint of fluidity of the paste.

  The volume ratio of the organic vehicle is, for example, 30 to 80% by volume, preferably 40 to 75% by volume, more preferably 50 to 70% by volume (particularly, based on the entire volume of the resistor paste (solid content or nonvolatile content). 55 to 65% by volume).

  The mass ratio of the organic vehicle is, for example, about 5 to 200 parts by mass, preferably 10 to 150 parts by mass, and more preferably 20 to 100 parts by mass (particularly 30 to 80 parts by mass) with respect to 100 parts by mass of the conductive component. is there. When combining an organic binder and an organic solvent, the proportion of the organic binder is 5 to 80% by mass, preferably 10 to 50% by mass, more preferably 15 to 40% by mass (particularly 20 to 40% by mass) based on the entire organic vehicle. %) Degree.

(Other additives)
For resistor pastes, conventional additives such as colorants (dyes and pigments), hue improvers, dye fixing agents, gloss imparting agents, metal corrosion inhibitors, stabilizers (antioxidants, UV absorbers, etc.) , Surfactants or dispersants (anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, etc.), dispersion stabilizers, viscosity modifiers or rheology modifiers, humectants, thixotropics A property-imparting agent, leveling agent, antifoaming agent, bactericidal agent, filler and the like may be contained. These additives can be used alone or in combination of two or more.

  The resistor paste is not particularly limited as long as a paste containing the above components can be obtained, but can usually be prepared by dispersing a conductive component, an inorganic binder component, and a resistance adjusting component in an organic vehicle by a conventional method.

[Resistor and its manufacturing method]
The resistor of the present invention can be obtained by firing a resistor paste. Usually, a coating process for applying a resistor paste on a substrate, and the resulting coating film is applied to a low-melting glass under an inert gas atmosphere. It is obtained by a production method including a firing step of firing at a temperature equal to or higher than the softening point of the particles.

  In the coating process, the substrate is not particularly limited as long as it is a bakable material, for example, various materials such as semiconductors (ceramics such as silica, alumina, and aluminum nitride), glass, metals and other inorganic materials, and engineering plastics. Organic materials such as can be used. Among these substrates, a heat resistant substrate, a ceramic green sheet, and the like are widely used, and a ceramic substrate such as an alumina substrate or an aluminum nitride substrate is preferable from the viewpoint of excellent adhesion to a resistor paste.

  What is necessary is just to select the thickness of a board | substrate suitably according to a use, for example, 0.001-10 mm, Preferably it is 0.01-5 mm, More preferably, it is about 0.05-3 mm (especially 0.1-1 mm). May be.

  Examples of resistor paste coating methods include flow coating, spin coating, spray coating, screen printing, flexographic printing, casting, bar coating, curtain coating, roll coating, gravure coating, Examples thereof include a dipping method, a slit method, a photolithography method, and an ink jet method. The coating may be formed on the entire surface of the substrate, but is usually formed on a part of the surface of the substrate in a pattern or the like. When a pattern is formed (drawn) with a coating film, a sintered pattern (sintered film, metal film, sintered body layer, conductor layer) can be formed by firing the formed pattern (drawn pattern). The drawing method (or printing method) for drawing the pattern (coating layer) is not particularly limited as long as it is a pattern forming printing method. For example, a screen printing method, an ink jet printing method, an intaglio printing method (for example, Gravure printing method), offset printing method, intaglio offset printing method, flexographic printing method and the like. Of these methods, the screen printing method and the like are preferable.

  After coating, it may be naturally dried, but may be dried by heating. The heating temperature can be selected according to the type of the organic solvent, and is, for example, about 50 to 200 ° C, preferably 60 to 150 ° C, and more preferably about 80 to 120 ° C. The heating time is, for example, about 1 minute to 3 hours, preferably about 5 minutes to 2 hours, and more preferably about 10 minutes to 1 hour.

  The coated coating film is subjected to a firing step of heating (or firing or heat treatment) at a predetermined temperature, whereby a resistor is obtained.

  In the firing step, the firing temperature may be any metal as long as it can sinter the metal that is the conductive component and is not less than the softening point of the low-melting glass particles, for example, 500 ° C. or higher (eg, 500 to 2000 ° C.), preferably 550 It is 1500 degreeC, More preferably, it is about 600-1200 degreeC (especially 700-1100 degreeC) grade. The heat treatment time (heating time) may be, for example, 1 minute to 48 hours, preferably 5 minutes to 8 hours, more preferably about 10 to 120 minutes, depending on the heat treatment temperature and the like. When applied to a fired ceramic substrate, the resistor of the present invention may be fired alone, or when applied to an unfired ceramic green sheet or sandwiched, fired simultaneously with the ceramic green sheet. May be.

  Firing is performed in an inert gas (for example, nitrogen gas, argon gas, helium gas, etc.) atmosphere, and is particularly preferably performed in a nitrogen atmosphere.

  The average thickness of the obtained resistor can be appropriately selected from the range of about 0.1 to 500 μm depending on the application, and is, for example, 0.2 to 100 μm, preferably 0.5 to 50 μm, and more preferably 1 to 30 μm ( In particular, it may be about 3 to 25 μm).

  The resistor according to the present invention has a volume resistivity of low / medium resistance of 200 μΩ · cm or more, which has been recently demanded, for example, 200 to 100,000 μΩ · cm (surface resistance of 10 μm thickness: 200 mΩ / □ to 100Ω / □). And is particularly effective in the range of 500 to 50,000 μΩ · cm, which is particularly useful.

  Furthermore, the resistor of the present invention has an absolute value of resistance value temperature dependency (TCR) of, for example, 500 ppm / ° C. or less, preferably 300 ppm / ° C. or less, more preferably 200 ppm / ° C. or less. Therefore, the resistor of the present invention has small temperature dependency and excellent stability.

  In the present invention, the volume resistivity and TCR can be measured by the methods described in the examples described later.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. In the following examples, measurement methods for each physical property and materials used in the examples are shown below.

[Volume resistivity and stability of resistance]
As a sample for evaluation, the resistance film (baked film) obtained in the example and the comparative example was allowed to stand for 30 minutes or more in an atmosphere having a temperature of 25 ± 3 ° C. and a humidity of 65 ± 10% RH. The resistance value of the film was measured. Moreover, the thickness of the resistance film was measured with a stylus type film thickness meter to determine the volume resistivity.

(Volume resistivity)
About the resistor obtained by the Example and the comparative example, 10 samples were measured, respectively, and the average value was made into volume resistivity.

(Resistance variation)
A numerical value obtained by dividing the value obtained by subtracting the minimum value from the maximum value among the volume resistivity of 10 samples was determined as the size of the variation, and the propriety was determined according to the following criteria.

○: Variation is 0.2 or less ×: Variation exceeds 0.2

[TCR]
The sample for evaluation was placed in a thermostatic bath at 125 ° C. and allowed to stand for 30 minutes or more, and then the resistance value of the resistance film was measured by a four-terminal method. The rate of change with respect to the resistance value and the resistance value measured at 25 ° C. was obtained and evaluated according to the following criteria.

TCR = [{average resistance value at 125 ° C.−average resistance value at 25 ° C.} / {Average resistance value at 25 ° C. × (125 ° C.−25 ° C.)} × 10 ⁶ (ppm / ° C.)
(Standard)
○: TCR is within ± 300 ppm / ° C. ×: TCR is less than −300 ppm / ° C. or exceeds 300 ppm / ° C.

[Firing film strength]
(Film scraping (scratch test))
In accordance with JIS-K5600-5-4, use a pencil with a hardness of 9H that has been sharpened so that the tip of the tip is flat. Set the pencil so that it is at an angle of 45 degrees with respect to the resistive film surface and apply a weight of 750g. And scratched and evaluated according to the following criteria.

○: The film is not scraped. Δ: The film is scratched and there is no significant scraping. ×: The film is scratched brittlely.

(Adhesion to substrate)
The resistance film was peeled off from the substrate with stainless steel tweezers and evaluated according to the following criteria.

○: Can not be peeled off even if a large force is applied. Δ: Can be peeled off if a certain amount of force is applied.

[Pattern collapse]
The appearance of the resistive film was observed with a microscope, and it was confirmed whether or not the low melting point glass component flowed out of the printing region or whether the printed pattern was largely broken by the melt flow of the low melting point glass component, and was evaluated according to the following criteria.

◯: The fired film is good and has a uniform shape. ×: The glass component flows out of the printing region, or the printing pattern is largely broken.

[Swelling]
Whether the resistive film was swollen with a loupe (15 times) was observed and evaluated according to the following criteria.

○: No swelling occurs. ×: Swelling occurs.

[Comprehensive judgment]
Based on the determination of each item, the following comprehensive determination was made.

○: Each required item is good, and is excellent as a resistor material. △: Some items are inferior to the best form, but can be used as a resistor material. Unsuitable.

  In each determination, Δ or higher is regarded as acceptable.

[Materials used]
Alumina powder particle size 3 μm: alumina particles, “DAM-03” manufactured by Denki Kagaku Kogyo Co., Ltd., center particle size (D50) 3 μm, specific gravity 4
Alumina powder particle size 1 μm: Alumina particles, “ALO14PB” manufactured by High Purity Chemical Laboratory, center particle size (D50) 1 μm, specific gravity 4
Silica powder particle size 3 μm: “FB-3SDC” manufactured by Denki Kagaku Kogyo Co., Ltd., center particle size (D50) 3 μm, specific gravity 2.2
Silicon carbide powder particle size 7 μm: “Shinano Random # 2,000” manufactured by Shin-Etsu Chemical Co., Ltd., center particle size (D50) 7 μm, specific gravity 3.2
Copper powder particle size 0.3 μm: copper particles, “1030Y” manufactured by Mitsui Mining & Smelting Co., Ltd., center particle size (D50) 0.3 μm, specific gravity 8.9
Nickel powder particle size 0.4 μm: Nickel particles, “SNP-350E” manufactured by Sumitomo Metal Mining Co., Ltd., center particle size (D50) 0.4 μm, specific gravity 8.9
Zn-based glass powder particle size 3 μm: zinc-based glass particles (ZnO—SiO ₂ —B ₂ O—R ₂ O (R is an alkali metal), softening point 575 ° C., center particle size (D50) 3 μm, specific gravity 3
Organic vehicle: 30% by mass of acrylic resin prepared by dissolving acrylic resin in a mixed solvent of terpineol and butyl carbitol acetate (mass ratio 1/1), specific gravity 1
Alumina substrate: “96% alumina substrate” manufactured by Nikko Corporation.

(Preparation of composite particles)
As the non-conductive particles (non-conductive inorganic particles), the above-mentioned alumina powder (center particle diameters 1 μm and 3 μm) was used. The surface of these alumina powders was subjected to copper plating, nickel plating, and alloy plating of copper and nickel by an electroless plating method. Specifically, in each electroless plating, first, the non-conductive particles were dispersed and degreased and washed in the plating pretreatment liquid while stirring. Subsequently, after the plating catalyst nucleus was adsorbed, it was immersed in a plating solution of each composition for a predetermined time to deposit a metal on the surface of the non-conductive particles. Finally, these particles were dried to obtain the desired composite particles. The mass percentage of the metal layer (plated film) was determined from the mass of the alumina powder before plating and the mass of the particles after plating. Further, the thickness of the metal layer was calculated from this mass percent.

  When the composite particle powder thus produced was observed with an SEM, it was confirmed that there was no aggregate or abnormal precipitation. Further, the prepared composite particles were embedded in an epoxy resin and cured, cut with a diamond blade and then polished to expose the cross section of the particles. This cross section was observed and elementally analyzed by SEM-EDX, and it was confirmed that the metal layer covered the alumina powder surface.

  Among the obtained composite particles, composite particles provided with the following four types of metal layers (shells) were obtained as composite particles using alumina powder (core) having a particle size of 3 μm.

Cu plating with a thickness of about 0.15 μm (Cu ratio in composite particles: 25% by mass)
Ni plating with a thickness of about 0.15 μm (ratio of Ni in the composite particles: 25% by mass)
Ni plating with a thickness of about 3 μm (ratio of Ni in the composite particles: 94% by mass)
Alloy of Cu and Ni having a thickness of about 0.4 μm (Cu: Ni = 6: 4 (mass ratio)) plating (ratio of alloy in composite particles: 50 mass%)
As composite particles using alumina powder (core) having a particle size of 1 μm, composite particles provided with Ni plating (ratio of Ni in the composite particles: 40 mass%) as a metal layer (shell) with a thickness of about 0.1 μm. was gotten.

(Preparation of resistor paste)
In each of the examples and comparative examples, the materials weighed at the blending ratios shown in Table 1 were mixed with a mixer, and then mixed uniformly with three rolls (manufactured by EXAKT (Germany)). A resistor paste was prepared.

(Production of resistor)
The prepared resistor paste is screen-printed with a 1 x 10 mm rectangular resistor pattern on a 96% alumina substrate on which a thick film copper electrode has been formed so that 4-terminal measurement is possible, and the printed substrate is blown dry at 100 ° C. After removing the solvent by drying for 20 minutes in a machine, it was put into a belt furnace and fired in a nitrogen atmosphere at a peak temperature of 900 ° C. and a peak temperature holding time of 10 minutes (total charge-discharge time of 60 minutes).

Examples 1-4
The particle | grains which gave Ni plating (25 mass%, thickness about 0.15 micrometer) were used for the surface of the alumina powder of a particle size of 3 micrometers. Moreover, copper powder and / or nickel powder were added in order to vary the conductive component volume ratio in order to adjust the Cu: Ni ratio. Further, the inorganic binder volume ratio was set at 15%. Using these pastes, a resistor was prepared by the above-described method, and each physical property was evaluated. As shown in Table 1, the smaller the conductive component volume ratio, the higher the volume resistivity. The larger the value, the lower the volume resistivity. Also, the resistance value variation was small, and good results were obtained. This is because alumina powder cannot originally participate in the formation of the conduction path, but rather inhibits its formation, but by providing a metal layer on the surface, the surface helps the stable formation of the conduction path, and the inside is insulated. This is to play a role of resistance adjustment. Good results were obtained for other items.

Example 5
Implemented except that the plating metal species on the surface of the alumina powder was replaced with Cu (25% by mass, thickness of about 0.15 μm), the metal powder for adjusting the Cu: Ni ratio was Ni, and a paste was prepared with the composition shown in Table 1. Resistors were produced and evaluated in the same manner as in Examples 1 to 4. As shown in Table 1, good results were obtained for each item.

Reference example 1
Replace the metal layer of alumina particles with Cu and Ni alloy plating (50% by mass, thickness of about 0.4 μm), and do not add copper powder or nickel powder (metal layer covering all conductive components on the surface of non-conductive particles) A resistor was manufactured and evaluated in the same manner as in Examples 1 to 4 except that. As shown in Table 1, good results were obtained even when all the conductive components were metal layers covering the surface of the non-conductive particles, but the fired film strength was slightly low, and there was no significant scratch in the scratch test. Has entered. However, it was at a level that could be used practically.

Example 6
A resistor was prepared and evaluated in the same manner as in Examples 1 to 4 except that the paste was prepared with the composition shown in Table 1 using both the Cu plating particles and the Ni plating particles described above. As shown in Table 1, good results were obtained.

Example 7
The composite particles are replaced with particles of 1 μm alumina powder Ni-plated (40% by mass, thickness of about 0.1 μm), and alumina particles (1 μm) not covered with a metal layer are also added as a resistance adjustment component Then, a resistor was prepared and evaluated in the same manner as in Examples 1 to 4 except that a paste was prepared with the composition shown in Table 1. As shown in Table 1, although high volume resistivity was shown, the resistance value variation was small and good results were obtained.

Examples 8 and 9
Example 1 except that composite particles having a thick metal layer (Ni plating layer) were used, alumina particles (3 μm) were also added as a resistance adjusting component in Example 9 , and pastes were prepared with the compositions shown in Table 1. Resistors were prepared and evaluated in the same manner as in No. 4. As shown in Table 1, good results were obtained.

Example 10
The composite particles were replaced with particles obtained by subjecting the surface of alumina powder having a particle size of 1 μm to Ni plating (40% by mass, thickness of about 0.1 μm), and the proportion of the inorganic binder was increased to prepare a paste with the composition shown in Table 1. A resistor was prepared and evaluated in the same manner as in Examples 1 to 4 except for the above. As shown in Table 1, good results were obtained.

Examples 11 and 12
Except that the composite particles were replaced with particles obtained by applying Ni plating (39% by weight, thickness of about 0.15 μm) to the surface of silica powder having a particle size of 3 μm, pastes were prepared with the compositions shown in Table 2 in Examples 1 to Resistors were prepared and evaluated in the same manner as in Example 4. As shown in Table 2, good results were obtained.

Examples 13 and 14
Example 1 except that the composite particles were prepared by applying Ni plating (20% by weight, thickness of about 0.2 μm) to the surface of silicon carbide powder having a particle size of 7 μm and preparing a paste with the composition shown in Table 2. Resistors were prepared and evaluated in the same manner as in -4. As shown in Table 2, good results were obtained.

Comparative Examples 1-5
A resistor was prepared and evaluated in the same manner as in Examples 1 to 4 except that non-conductive particles (alumina particles) not covered with a metal layer were used as a resistance adjusting component, and a paste was prepared with the composition shown in Table 2. Went. As shown in Table 2, the resistance can be arbitrarily adjusted according to the amount added, but the resistance variation was larger than that of the example (Example 1 and Comparative Example 1, Example 2 and Comparative Example 2, Example 3). And Comparative Example 3, Example 5 and Comparative Example 4, and Example 7 and Comparative Example 5 correspond respectively). The reason why the resistance is high instead of the volume ratio of the resistance adjusting component in Comparative Example 5 is that the particle diameter of the alumina particles used for the resistance adjusting component is small.

  In Tables 1 and 2, the ratio of each component of composite particles, non-conductive particles, metal particles, inorganic binder, and organic vehicle is based on mass unless otherwise specified.

  The resistor paste of the present invention includes a chip resistor, a resistor built-in module, a resistor built-in substrate, a thick film resistor such as a ceramic heater, and a resistor including the thick film resistor (for example, a resistor and a copper electrode). Resistors etc.) or electronic parts.

Claims (14)

Low melting point glass particles having a conductive component formed of a metal including copper and nickel, a resistance adjusting component formed of non-conductive inorganic particles that are not melted or thermally decomposed at the firing temperature, and a softening point lower than the firing temperature. A resistor paste including the formed inorganic binder and an organic vehicle for dispersing these components, wherein at least a part of the conductive component covers at least a part of the resistance adjusting component, A composite particle in which at least a part of the surface of the conductive inorganic particle is coated with a conductive layer is formed, and the conductive component includes the conductive layer and the metal particle, and the ratio of the metal particle is 100 mass of the composite particle. against part, Ri 17-243 parts by der, the non-conductive inorganic particles are alumina, silica, titanium oxide, at least one member selected from silicon carbide, tempered Resistance value of the resistor is, 200~100,000μΩ · cm der Ru resistor paste.   The resistor paste according to claim 1, wherein the conductive layer contains copper and / or nickel.   The resistor paste according to claim 1 or 2, wherein the conductive layer covers 50% or more of the entire surface of the nonconductive inorganic particles, and the thickness of the conductive layer is 0.05 to 5 µm.   The resistor paste according to claim 1, wherein the conductive layer is formed by electroless plating.   Furthermore, the resistor paste in any one of Claims 1-4 containing the nonelectroconductive inorganic particle which is not coat | covered with the conductive layer.   The volume ratio of the conductive component, the resistance adjusting component and the inorganic binder component is 10 to 80% by volume, 1 to 75% by volume and 5 to 50% by volume with respect to the total volume of the conductive component, the inorganic binder component and the resistance adjusting component, respectively. The resistor paste according to claim 1, which is%.   The resistor paste according to any one of claims 1 to 6, wherein the nonconductive inorganic particles have a center particle size (D50) of 0.05 to 20 µm and are spherical metal oxide particles.   The conductive component is an alloy of copper and nickel, or at least two selected from the group consisting of copper, nickel and an alloy of copper and nickel, and the mass ratio of copper and nickel is copper / nickel. The resistor paste according to any one of claims 1 to 7, wherein = 90/10 to 30/70.   The resistor paste according to any one of claims 1 to 8, wherein an absolute value of resistance value temperature dependency (TCR) of the fired resistor is 300 ppm / ° C or less.   The manufacturing method of a resistor including the baking process which bakes the resistor paste in any one of Claims 1-9 in the inert gas atmosphere at the temperature more than the softening point of a low melting glass particle.   The production method according to claim 10, wherein the inert gas is nitrogen gas.   The resistor obtained by the manufacturing method of Claim 10 or 11.   A thick film resistor comprising the resistor according to claim 12. An electronic component comprising the resistor according to claim 12.